1. Field of the Invention
The present invention relates to a cleaning apparatus for use in connection with vacuuming carpets and other flooring. The brushless vacuum cleaner has particular utility in connection with cleaning a carpet with pulsed air flow for agitation, thereby reducing the wear on a carpet caused by beater brushes in conventional vacuums.
2. Description of the Prior Art
Conventional vacuum cleaners make use of vacuum pressure to draw air and debris adjacent to the vacuum cleaner head into a collection device. Many different forms of vacuum cleaner heads have been developed in the past to aid the debris collection effort. Beater brushes or bars are typical examples of these cleaner heads. A beater brush is used to agitate an area of the surface to be cleaned in an attempt to loosen debris that might not otherwise be susceptible to being lifted by the suction force of the vacuum cleaner. However, beater brushes inflict wear on surfaces over time and can cause premature replacement of floor coverings such as carpet. The brushes themselves also suffer wear and require eventual replacement to perform at an acceptable level. Therefore, a vacuum cleaner that employed a method other than beater brushes for loosening debris would be of interest to any household or business employing a vacuum for cleaning floor surfaces.
The use of brushless vacuum cleaners is known in the prior art. For example, U.S. Pat. No. 6,052,861 to Kris D. Keller discloses a vacuum system in which hot air is discharged from the vacuum cleaner, moves across the surface being cleaned, and is subsequently drawn back upwardly through the intake plenum. A fluid discharge line is positioned within the intake plenum and includes fluid discharge openings oriented to direct pumped fluid downwardly and angularly toward the bottom end of the hot air discharge plenum to impinge upon the surface being cleaned and to be subsequently drawn into the intake plenum. However, the Keller '861 device uses a fluid for cleaning purposes which would not be suitable for frequent use in cleaning carpets or other fiber based flooring materials. Additionally, the heat discharged by the Keller '861 vacuum system would cause premature wear on carpets and other flooring materials.
U.S. Pat. No. 5,562,779 to Allan W. Allaway, Ian Blair, and Allan J. Seefeld discloses a device and method for cleaning particulate material that is used for renovating synthetic grass playing surfaces which optionally include a layer of particulate material, such as sand. The device consists of a plenum chamber which directs a fast moving jet of air against the particulate to dislodge it from the surface and direct it into a manifold. The manifold partially surrounds the plenum chamber and is designed to separate out the fine particles, directing them to a collection area, while laying the coarse particulate back on the surface. However, the Allaway, et al. '861 device returns some of the particulate matter to the surface being cleaned; therefore, it would not be useful for cleaning of residential or commercial flooring. Furthermore, the Allaway, et al. '861 device contains a filtering mechanism which would increase the complexity and, thus, the cost of the device over other vacuum type floor cleaners.
Similarly, U.S. Pat. No. 5,450,649 to Kenneth J. Turnbull discloses a collection device having a duct for transporting material entrained in a stream of pressurized primary air from a collection mouth at an upstream end of the duct to a downstream region of the duct for collection. The device has a primary air outlet appropriately directed to entrain dirt on the surface to be cleaned into the air collection stream and a secondary air outlet which can be used to blow debris into a pile for subsequent collection. However, the Turnbull '649 device would be difficult for use in cleaning corner areas of the room since the secondary air outlet would direct pressurized air away from the apparatus, thus scattering debris away from the air collection stream. Furthermore, the plenum and duct formation is a rigid construction that does not allow the user to vertically adjust the unit for ease of use or storage purposes. Finally, the Keller '861 system allows only a single direction for the air stream generated by the unit, which might not loosen as much debris from the surface to be cleaned as air streams originating from multiple directions.
U.S. Pat. No. 5,970,574 to Thomas B. Thrash, Jr. discloses an apparatus and method for cleaning hard surfaces by removing and containing waste. The Thrash apparatus produces a high velocity airflow to dislodge debris from the surface and high velocity streams of cleaning fluid for cleaning the surface. However, the Thrash, Jr. '574 apparatus is intended for use on hard surfaces and not on carpeted surfaces. Moreover, frequent use of the Thrash, Jr. '574 device on carpeted surfaces could cause premature wear on the carpet.
Likewise, U.S. Pat. No. 5,280,667 to John E. Coathupe discloses a collection device that comprises a pair of air outlet pipes surrounding an air inlet duct, all of which are connected to a collection head. Air is forced down the pipes via a motor and fan arrangement to dislodge debris from the surface to be cleaned. The end of each pipe is curved toward the air inlet duct, aiding the entrainment of debris into the air stream flowing into the air inlet duct. However, the Coathupe '667 device would be difficult to move across a surface since it does not provide wheels or another arrangement on the bottom of the device for ease of movement. In addition, the placement of the filter bag on the Coathupe '667 device might allow microscopic particles to escape into the air that is breathed by the user. This could cause difficulty in breathing, especially for individuals with asthma or allergies.
Lastly, U.S. Pat. No. Des. 392,430 to Francesco Piccaluga and Aldo Piccaluga discloses the ornamental design for an upright vacuum cleaner. However, the Piccaluga, et al. '430 device employs a beater brush which could cause premature wear and damage to the floor cover being cleaned. Additionally, the Piccaluga, et al. '430 patent makes no indication that the device would be capable of cleaning corners through the use of angled air streams or special suction units located in the front corners of the device.
While the above-described devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not describe a floor cleaning device that uses air agitation in multiple directions to loosen debris for collection via an intake plenum in the device, thus allowing the user to effectively clean not only the flat surface but also the corners of a room. The Keller '861 and Thrash, Jr. '574 devices use a fluid for cleaning purposes and would not be suitable for frequent use in cleaning carpets or other fiber based flooring materials. Moreover, frequent use of either the Thrash, Jr. '574 or Keller '861 device on carpeted surfaces could cause premature wear of the carpet due to the high velocity fluid streams used by the Thrash, Jr. '574 device and the heat and fluid discharged by the Keller '861 device. The Piccaluga, et al. '430 device could also cause premature wear of the floor covering due to the use of a beater brush for disloding debris. Additionally, the Allaway, et al. '861 device returns some of the particulate matter to the surface being cleaned; therefore, it would not be useful for cleaning of residential or commercial flooring. The Turnbull '649 and Piccaluga, et al. '430 devices would not be advantageous for cleaning the corners of a room. The secondary air outlet of the Turnbull '649 device directs pressurized air away from the apparatus, thus scattering debris away from the air collection stream, while the Piccaluga, et al. '430 patent fails to address the issue. Furthermore, the Turnbull '649 device allows only a single direction for the air stream generated by the unit, which would not loosen as much debris from the surface to be cleaned as air streams originating from multiple directions. The rigid construction of the plenum and duct of the Turnbull '649 device does not allow the user to vertically adjust the unit for ease of use or storage purposes. The Coathupe '667 device would be difficult to move since no wheels are provided on the bottom of the device. Additionally, the placement of the filter bag on the Coathupe '667 device might allow microscopic particles to escape into the air that is breathed by the user. Finally, the Allaway, et al. '861 device contains a filtering mechanism which would increase the complexity and, thus, the cost of the device over other vacuum type floor cleaners.
Therefore, a need exists for a new and improved brushless vacuum cleaner that can be used for easily and effectively cleaning corners and flooring surfaces while decreasing the amount of wear and tear on the floor covering that might be caused by a conventional vacuum cleaner with a beater brush. In this regard, the present invention substantially fulfills this need. In this respect, the brushless vacuum cleaner according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of cleaning a carpet with pulsed air flow for agitation, thereby reducing the wear on a carpet caused by beater brushes in conventional vacuums.